Carrier Bryant electric furnace blower runs non stop


  #1  
Old 02-02-13, 08:32 AM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
Carrier Bryant electric furnace blower runs non stop

I have an older model Carrier Bryant electric furnace. I recently replaced the control board and inducer blower motor.

The furnace went off yesterday and it wouldn't come back on. It was 11 degrees.
The temperature was 66. I was able to turn it back on. It heated the house up to 70 degrees eventhough the thermostat was set to 75.

The blower runs non-stop and it blows warm air but not enough to heat the house above 70 degrees.

When I woke up this morning the temperature was at 67 degrees and the blower was still running and blowing mildly warm air.

I didn't have this issue previously.

I tapped the limit switch several times just in case it was stuck.

Any ideas or suggestions are appreciated!
 
  #2  
Old 02-02-13, 08:59 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,530
Received 95 Upvotes on 88 Posts
This problem with air handlers is the sequencer 90% of the time.

BUT....

You have a gas furnace if you have an inducer motor and you have posted in the wrong forum.
 
  #3  
Old 02-02-13, 09:40 AM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
Do you have an inducer? If so, you don't have an electric furnace.
 
  #4  
Old 02-02-13, 10:40 AM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
My mistake. Thank you for your feedback.
 
  #5  
Old 02-02-13, 12:15 PM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
Wait, we want to help, but you must answer our question.
 
  #6  
Old 02-02-13, 08:01 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
It does have an inducer. It blows air nonstop.
 
  #7  
Old 02-02-13, 08:04 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
BTW, the flame stays lit all the time.
 
  #8  
Old 02-02-13, 08:26 PM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
so is the furnace overheating the house if the flame AND the blower stays on all the time?
 
  #9  
Old 02-02-13, 08:30 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
It reaches the desired temperature and it continues to run nonstop and the flame stays lit.
 
  #10  
Old 02-02-13, 08:31 PM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
remove W wire from the thermostat does the flame shut off and eventually the blower?
 
  #11  
Old 02-02-13, 08:43 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
I removed the W wire from the thermostat and both the flame and blower shut off in under a minute.
 
  #12  
Old 02-02-13, 08:46 PM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
so, on most digital thermostats even though the indoor temp may read the same as the setpoint it is actually reading in tenths of a degree. SO your temp should never change on the thermostat and the furnace should cycle as it is needed to maintain the setpoint. If your home is overheating beyond the setpoint then that is a different situation in which it sounds like you need a new thermostat.
 
  #13  
Old 02-02-13, 08:49 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
The temp never goes above 72 degrees even if I set it to 75.
 
  #14  
Old 02-02-13, 08:52 PM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
Your furnace may not be sized properly to heat your home that warm depending upon the outdoor temp. Or there may be an issue with the gas pressure from the utility or at the gas valve on your furnace. These are checks that should be done by a professional.
 
  #15  
Old 02-02-13, 08:58 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
I happen to have a spare thermostat. Do you recommend I replace it?
 
  #16  
Old 02-03-13, 05:51 AM
hvactechfw's Avatar
Member
Join Date: Jan 2011
Posts: 5,491
Upvotes: 0
Received 4 Upvotes on 4 Posts
If you already have a spare then it won't hurt to try it.
 
  #17  
Old 02-03-13, 08:47 AM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 6,530
Received 95 Upvotes on 88 Posts
Measuring the return air temperature at the filter grill and measuring the return air temperature a couple of inches from the furnace intake will probably prove that you have a large leak in your return air ducting.

Measuring the supply air temperature at the furnace while you are there will tell you the temperature rise.

The rated rise is listed on the furnace nomenclature (tag).

A digital "meat" thermometer should be used for these measurements.
 
  #18  
Old 03-03-13, 05:52 PM
M
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 8
Upvotes: 0
Received 0 Upvotes on 0 Posts
A month later and my furnace is still having the issues.
I replaced the thermostat and made sure it's set on auto.
The blower motor and flame are constantly on.
It blows warm air and then it blows cold air and sometimes it doesn't blow any. I'm assuming it's either blowing cold air or no air to prevent the furnace from overheating...if that term applies.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: